How can you calculate an empirical formula?
- Change % to grams.
- change grams to moles
- change moles to a mole ratio, and divide by smallest mol quantity to get whole numbers.
- write as a formula.
% => grams => moles => ratio => normalize => adjust => empirical ratio!
1) Given data in % per hundred wt drop the % and tag with grams.
2) Convert grams to moles (divide by formula wt)
3) set ratio of moles
4) normalize => divide by smaller mole value
5) adjust => if normalized values are fractions of 0.25 or 0.75 then multiply by 4; if normalized values are fractions of 0.50 then multiply by 2
6) adjusted ratio => empirical ratio => empirical formuls
The following is an example: